1. Field of the Invention
This invention pertains generally to optical head devices, systems and methods for reading optical media, and more particularly to a near-field optical system and method wherein one or more semiconductor lasers and a slider are made and used as a single, integrated monolithic device.
2. Description of the Background Art
The optical head of an optical read/write system can operate as a “flying head” wherein the optical head does not contact the adjacent optical medium, but is positioned close to the optical medium and separated by an air gap. The optical head includes an aerodynamically designed slider with an air bearing surface for maintaining an air cushion between the optical head and the optical medium. One or more solid state lasers are mounted on the slider and are positioned to read and/or write onto the optical medium. The slider is typically mounted on a read arm by a spring mechanism, with the bias of the spring mechanism and the aerodynamic shape of the slider determining the distance between the optical head and optical medium.
Conventionally, the solid state laser and slider are separate components made of different materials. The slider, for example, may comprise a metallized SiC or TiC/Al2O3 body which has been appropriately shaped for aerodynamic properties. A solid state laser or lasers are mechanically attached to the slider subsequent to its fabrication. An exemplary prior art attachment process involves careful positioning of the slider on an optical flat, applying a suitable quantity of adhesive or solder to the appropriate locations on the slider, and then urging the laser or lasers along the optical flat into position using micropositioners or microtranslation apparatus. This procedure is generally carried out under an optical microscope. When the adhesive cures, the emission face of the laser should be essentially flush with the slider air-bearing surface.
The above mechanical attachment procedure is difficult and time-intensive. The machining and mechanical alignment tolerances for such mechanical attachment are high, generally on the order of 15 nanometers. Improper attachment of the laser and slider cannot generally be corrected. The preparation of optical heads in this manner has thus involved considerable expense.
There is accordingly a need for an optical head apparatus and method which avoids complex, difficult and expensive mechanical attachment procedures for securing solid state lasers to a slider. The present invention satisfies this need, as well as others, and generally overcomes the deficiencies found in the background art.